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arXiv · 1910.12407

An improved bound for strong unitary uncertainty relations with refined sequence

Jing Li·Sujuan Zhang·Lu Liu·Chen-Ming Bai
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Abstract

We derive the lower bound of uncertainty relations of two unitary operators for a class of states based on the geometric-arithmetic inequality and Cauchy-Schwarz inequality. Furthermore, we propose a set of uncertainty relations for three unitary operators. Compared to the known bound introduced in Phys.Rev.A.100,022116(2019), the unitary uncertainty relations bound with our method is tighter, to a certain extent. Meanwhile, some examples are given in the paper to illustrate our conclusions.

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Jing Li, Sujuan Zhang, Lu Liu, Chen-Ming Bai. 2019-10-28. An improved bound for strong unitary uncertainty relations with refined sequence. https://doi.org/10.1088/1612-202x%2Fab5c22

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